Google's connected home devices and services rely on cameras, microphones and other sensors to provide helpful features and services. These sensors can detect things like motion and sound to protect your home and loved ones and make your lives more convenient and comfortable. And while they make our connected home devices more useful, we understand that you, your family and your friends need to trust that we'll handle your data responsibly.
We've published our commitment to privacy in the home where we've committed to the following:
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When our connected home devices include cameras, microphones, or environmental or activity sensors that detect information about your home environment, we'll list these hardware features in the device's technical specifications — whether or not they're enabled.
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We'll also clearly explain what types of information these sensors send to Google, as well as examples of how we use that information, to help you better understand their purpose.
We've published this sensors guide as part of these commitments. We'll continue to periodically update this sensors guide to add new devices, features and services, reflect changes to our existing offerings, or where applicable, provide additional details and information.
The current sensors in Google's connected home devices and services generally fall into the following categories:
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Camerasthat record video footage and still images and detect what's happening in the home.
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Microphonesthat record audio and can detect specific sounds or motion nearby.
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Activity sensorsthat detect activity or changes to the physical state of the device, such as a door sensor that detects when a door opens, or an accelerometer that detects when a device is moved. Some activity sensors may also detect the presence or movement of people in your home.
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Environmental sensorsthat determine external properties of the surrounding environment — such as temperature, humidity, light, or smoke — and that can help monitor the conditions inside or around your home.
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Control sensorsthat enable control of a device, such as a touch-sensitive button, or a magnetic sensor to detect the position of the ring on the Nest Learning Thermostat.
Google's connected home devices may also contain additional sensors that monitor device operation. For example, internal device sensors can detect when a device's battery is running low, when it's overheating, or other conditions that can affect the ability of the device to operate as intended. We've excluded sensors that collect only such diagnostic data from this sensors guide. In addition to enabling the features and services described, the data from the sensors listed below may also be used to perform device performance and diagnostic functions.
Types of sensors, what they measure, and examples of uses
Cameras and Microphones
Nest Cam, Nest Cam IQ, Nest Cam (battery), Nest Cam with floodlight, Nest Cam (indoor, wired), Nest Cam Indoor (wired, 3rd gen), Nest Cam Outdoor (wired, 2nd gen), Nest Doorbell (wired)/Nest Hello, Nest Doorbell (wired, 2nd gen), Nest Doorbell (wired, 3rd gen), Nest Doorbell (battery), and Nest Hub Max
- Checks what's happening near the camera. Also used to detect certain types of activity, so you get an alert when a person or motion is detected near the camera.
- Depending on the camera model, where you live, and whether or not you have a Google Home Premium or Nest Aware subscription, the camera can be used to identify a face you've told it to recognize and send an alert when it recognizes someone you know or a stranger. Camera events can be used to start home automations.
Nest Hub Max
In addition to the built-in Nest Cam features described above, Nest Hub Max also uses the camera to enable video calling, personalization with Face Match, and Quick Gestures for easy device control. Additional features that use the camera may be added over time.
Nest Cam, Nest Cam IQ, Nest Cam (battery), Nest Cam with floodlight, Nest Cam (indoor, wired), Nest Cam Indoor (wired, 3rd gen), Nest Cam Outdoor (wired, 2nd gen), Nest Doorbell (wired)/Nest Hello, Nest Doorbell (wired, 2nd gen), Nest Doorbell (wired, 3rd gen), and Google Nest Doorbell (battery)
- Hears what's happening near the camera. Also used to detect certain types of sounds so you can get an alert when a person or motion is detected near the camera.
- The microphone is also used for the Talk and Listen feature that lets you talk to anyone near the camera. Nest Cam IQ Indoor also allows you to talk to your voice assistant (if you have enabled that feature).
Google Home, Google Home Mini, Google Home Max, Google Nest Hub, Google Nest Hub (2nd gen), Google Nest Hub Max, Google Nest Mini, and Google Nest Audio
- Allows you to talk to your voice assistant, make calls, and with a Google Home Premium or Nest Aware subscription in certain regions, detect sounds like smoke alarms or glass breaking (if you have enabled that feature).
- Provides occupancy signals for home automation (such as presence-based automations), if you've enabled the feature.
Google Nest Wifi point
Allows you to talk to your voice assistant, make calls, and more. Detect occupancy for home automation (such as presence-based automations), if you've enabled the feature.
Google Chromecast Voice Remote and Google TV Streamer Voice Remote
Allows you to talk to your voice assistant, navigate apps on your TV, and provide voice input to apps.
Nest Protect
Used by the Sound Check and Safety Checkup features to make sure the speaker and alarm sound are operational. The microphone is not used for any other purpose and is off except when checking speaker and horn functionality.
Nest Hub, Nest Hub (2nd gen), Nest Hub Max, Nest Mini, and Nest Wifi point
Emits ultrasonic pulses from the speaker to detect proximity of a user for a more responsive and proactive device experience, such as triggering the display of media or device controls on the device.
Nest Hub (2nd gen)
When Sleep Sensing is enabled, listens for nearby sounds such as coughing and snoring that may disturb sleep.
Activity Sensors
Google Home Max
Adjust lights depending on speaker orientation.
Google Chromecast Voice Remote and Google TV Streamer Voice Remote
Detects the motion of the remote to initiate reconnecting with paired devices and facilitate interactions with other devices.
Nest Connect and Nest Protect
Currently unused. Included for potential future feature enhancements.
Nest Cam (battery), Nest Cam with floodlight, Nest Doorbell (battery)
Detects motion to wake up the device.
Nest Cam with floodlight
Detects motion to trigger the lights.
Nest Learning Thermostat and Nest Thermostat E
Nest may infer occupancy from detected motion for comfort optimization, energy saving, and home automation (such as Home/Away Assist or presence-based automations).
Nest Protect
Detects motion for home automation (such as Home/Away Assist or presence-based automations) and to turn on Pathlight when someone walks under Nest Protect.
All of the above devices where motion is detected
Detects motion to trigger home automations.
Nest Learning Thermostat
Detects motion near the thermostat in order to light up the display.
Nest Protect (1st generation)
Currently inactive.
Google Home, Google Home Mini, Google Nest Mini, Google Home Max, Google Nest Audio, Google Nest Hub, Google Nest Hub (2nd gen), Google Nest Hub Max, Google Nest Wifi point, Chromecast with Google TV, Google Chromecast Voice Remote, Google TV Streamer (4K), Google TV Streamer Voice Remote, Nest Temperature Sensor, Nest Learning Thermostat, Nest Thermostat E, Nest Thermostat, Nest Cam (battery), Nest Cam with floodlight, Nest Cam (indoor, wired), Nest Cam Indoor (wired, 3rd gen), Nest Cam Outdoor (wired, 2nd gen), Nest Doorbell (battery), Nest Doorbell (wired, 1st gen), Nest Doorbell (wired, 2nd gen) and Nest Doorbell (wired, 3rd gen)
Detects the presence of a device tag on another compatible Bluetooth-enabled device (such as letting you use Tile with your Google Home smart speaker ) to setup and enable various built-in features.
Nest Temperature Sensor, Nest Learning Thermostat, and Nest Thermostat E
Allows Nest Temperature Sensor to use Bluetooth to communicate with your thermostat.
Google Home, Google Home Mini, Google Nest Mini, Google Home Max, Google Nest Audio, Google Nest Hub, Google Nest Hub (2nd gen), Google Nest Hub Max, Google Nest Wifi point, Chromecast with Google TV, Google Chromecast Voice Remote , Google TV Streamer (4K), and Google TV Streamer Voice Remote
- Allows you to stream music playing on your Google speaker or display to your favorite Bluetooth-enabled speakers or headphones.
- Allows you to stream music from your mobile device (phone or tablet) or computer to your Google speaker or display .
- Allows you to stream music from your Google streaming device to your Bluetooth headphones and/or Bluetooth-enabled soundbar or speaker.
Nest Learning Thermostat (4th gen) and Nest Thermostat
Detects activity near the thermostat to light up the display.
Nest thermostat technical specifications
Nest Hub (2nd gen)
Detects movement and breathing which allows you to use Sleep Sensing . Detects movement so you can control media, alarms and timers using Quick Gestures. Detects occupancy for home automation (such as presence-based automations), if you've enabled that feature.
Environmental Sensors
Google Home and Google Home Max
Controls LED brightness.
Nest Hub, Nest Hub (2nd gen), Nest Hub Max
Controls display brightness and color calibration.
Nest Hub (2nd gen)
Measures ambient room light with Sleep Sensing to help you understand sleep environmental disturbances.
Nest Learning Thermostat, Nest Thermostat E, and Nest Thermostat
Controls display brightness and improve temperature sensor accuracy by detecting when the sun is shining on the thermostat.
Nest Cam IQ and Nest Doorbell (wired)/Nest Hello
Detects day or night to switch Night Vision off and on.
Nest Cam with floodlight
Detects day or night to trigger the lights only at dark.
Nest Protect
Detects when the room is dark so it can automatically turn on the Pathlight and Nightly Promise features.
Nest Protect
Detects dangerous levels of carbon monoxide in the air.
Nest Learning Thermostat, Nest Thermostat E, and Nest Thermostat
Detects ambient humidity for comfort optimization and control of whole-home humidifiers.
Nest Protect
Enables the Steam Check feature to reduce nuisance alarms caused by things like steam from your shower.
Nest Protect (1st generation)
Fire or smoke detection.
Nest Protect (2nd generation)
Fire or smoke detection.
Nest Hub (2nd gen)
Measures ambient room temperature with Sleep Sensing to help you understand sleep environmental disturbances.
Nest Learning Thermostat, Nest Thermostat E, Nest Heat Link E, Nest Temperature Sensor, Nest Thermostat
Estimates ambient room temperature for comfort optimization.
Nest Protect
Detects sudden rises in room temperature.
Control Sensors
Google Home, Google Home Mini, Google Nest Mini, Google Home Max, Nest Hub, Nest Hub (2nd gen), Nest Hub Max, Google Nest Audio, and Nest Thermostat
Used for device control and provides an occupancy signal for home automation (such as presence-based automations), if you've enabled that feature.
Google Nest Wifi point
Used for device control.
Nest Learning Thermostat (4th gen), Nest Learning Thermostat (3rd generation) and Thermostat E
Detects movement of the ring for manual thermostat control.
Nest Cam (battery), Nest Cam with floodlight, and Nest Doorbell (battery)
Detects tampering of the device. Detect when the device is being charged to disable the camera.
Nest Learning Thermostat (1st gen and 2nd gen)
Detects movement of the ring for manual thermostat control.
Nest ✕ Yale Lock
Detects whether the bolt is open or closed.
* This is a non-exhaustive list of examples of how sensors explained here are used in Google's connected home devices and services. Our goal is to help you better understand the purpose behind these sensors, and the different ways these sensors are used in our devices and services to offer helpful features and services.

